ci: Fix semver PR comment check for fork PRs

[schgoo]

Fork PRs have read-only GITHUB_TOKEN and cannot post comments. Trying to see if we can skip the sticky-pull-request-comment steps when the PR comes from a fork to avoid "Resource not accessible by integration" errors.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.0%. Comparing base (061e578) to head (812bd89).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #205   +/-   ##
=======================================
  Coverage   100.0%   100.0%           
=======================================
  Files         105      105           
  Lines        6761     6761           
=======================================
  Hits         6761     6761           

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[geeknoid]

So PRs from a fork won't get notified about semver breaks?

[schgoo]

So PRs from a fork won't get notified about semver breaks?

@geeknoid This is already true; the semver check fails regardless of semver breaks, and no comments are made, because the GITHUB-TOKEN for fork PRs has read-only access. I'm open to a better suggestion, though. For example, we could:

1. Also remove continue-on-error: true for the Semver Compatibility check, so it actually fails if the semver check fails.
2. Allow us to check in code to non-main branches.
3. Upload semver results as an artifact, and have a separate oxidizer repo-local workflow that triggers the PR comments (not sure how you'd do comment cleanup there, though).